The Division of Intramural Population Health Research {DIPHR) at the Eunice Kennedy Shriver National Institute of Child Health & Human Development {NICHD) designs and conducts original epidemiological, behavioral, and biostatistical research encompassing several research domains such as human reproduction and development, pregnancy and related complications, pediatric and adolescent health and behaviors, and methodologic research relevant for our mission. The Division comprises three intramural research branches, Epidemiology, Biostatistics & Bioinformatics, and Social and Behavioral Sciences, and its mission is to design and implement original research with the potential for high impact findings that impact public health. Under the developmental origins of health and disease {DOHaD) hypothesis, early life exposures can program an individual for health and chronic disease risk through cellular adaptations to biological processes. Prenatal exposures and genetic factors impact fetal growth and development and neonatal health, important determinants of life-long health and disease. We propose an approach to examine a) the father's role, b) placental determinants, and c) timing of delivery in relation to fetal and neonatal health and development. A cohort study will be performed to collect common data elements from approximately 7700 pregnant women and their neonates and approximately 3825 male partners with a randomized control trial conducted in women with gestational diabetes {approximately 720 women). African American women shall be oversampled (~4250). It is anticipated that multiple study sites shall be established. SCOPE The study site (Contractor) shall complete all activities pertaining to the preparation of the study materials, regulatory procedures, and training of site study staff relevant to the described cohort and trial. The preparatory activities will ready the study team, including the site, DCC, and NICHD members for successful Study initiation. Multiple sites shall establish a cohort consisting of approximately 7,700 pregnant women, of whom around 4250 (55%) are self-reported to be Black or African American. It is anticipated that about 50% of their male partners (n= approximately 3825) shall also participate in data collection. Women who enroll in the cohort early in pregnancy and are diagnosed with GDM (about 10%) shall be approached for randomization to timing of delivery. All other women diagnosed with GDM, regardless of having entered the cohort in the first trimester shall also be invited into the TIME trial to reach a randomization goal of a total of approximately 720 women with GDM .